Application of evolutionary algorithms to the definition of the optimal twin‐screw extruder configuration for starch cationization

Abstract

The twin‐screw configuration problem (TSCP) involves defining the location of a set of predefined screw elements of a corotating twin‐screw extruder configuration to optimize different, often conflicting, objectives. A multiobjective optimization methodology based on Evolutionary Algorithms was developed and applied to solve the TSCP. This methodology is used in starch cationization case studies, involving different screw elements and screw lengths. The results obtained, taking into consideration various conflicting objectives, such as minimizing the specific mechanical energy and maximizing output and reaction efficiency, have physical meaning and thus validate the methodology. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers

Multi-objective ant colony optimization for the twin-screw configuration problem

“…Due to the complexity of the flow and heat transfer in twin screw extruders and the need to generate sufficiently accurate predictions of the process response upon changing its main parameters, the authors developed a numerical modelling routine (Teixeira et al 2007(Teixeira et al , 2010. For the purposes of this work, this routine can assumed to be a "black box".…”

“…Thus, the modelling routine must (i) be capable of describing accurately the relevant flow and heat transfer phenomena, (ii) be sensitive to changes in geometrical or operational parameters and (iii) require moderate computational resources. A detailed description of the routine is given elsewhere (Teixeira et al 2007(Teixeira et al , 2010. It encompasses all steps from material inlet to die exit, including solids conveying under or without pressure, melting, melt conveying under or without pressure and die flow.…”

“…The method employs a Multi-Objective Evolutionary Algorithm (MOEA) (Deb 2001, Coello Coello et al 2007, denoted as Reduced Pareto Set Genetic Algorithm (RPSGA), that uses a clustering technique to simultaneously ensure the progression of the population of solutions in the direction of the Pareto-optimal front and the dispersion of the solutions along this front (Gaspar-Cunha et al 1997, Gaspar-Cunha 2000. The approach was successfully applied to the optimization of operating conditions (Gaspar-Cunha et al 2002), screw configuration (Gaspar-Cunha et al 2005) and, more recently, material manufacture via reactive extrusion (starch cationization (Teixeira et al 2010 and ε-caprolactame copolymerization (Gaspar-Cunha et al 2005, Teixeira et al 2010. The authors are unaware of other attempts to develop a scientific methodology to solve the TSCP.…”

A computer model for starve‐fed single‐screw extrusion of polymer blends

“…These studies have been discussed by Wilczyński et al . General review on modeling of polymer extrusion has been presented elsewhere …”

A composite model for an intermeshing counter‐rotating twin‐screw extruder and its experimental verification

“…Recently, Jiang et al have developed a global model for closely intermeshing counter‐rotating twin‐screw extruders with flood feeding. Studies on modeling for polymer extrusion has been recently summarized in the literature .…”